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View Full Version : 38-40 Chambers n Sizing Dies



DOUBLEJK
08-12-2006, 06:56 PM
Well I got a chance to fire the new Ruger Blackhawk today and it shoots the factory stuff from UltraMax O.K. was hopin' fer great with my own loads...
Now the problem...:???:
The brass fireforms to an almost no neck shape...I mean it really blows the shoulder farther foward....I also aquired 1 of those 1 of 500 Japchester 1892's in 38-40 to make a set and it fireforms them factory loads to a bit farther out shoulder yet...
I have a new set of LEE dies for it and with the sizing die screwed in to touch the shell holder it doesn't even come close to touching that shoulder....effectivelly neck sizing my fired cases only...
Are the factory loads really that far off or are my guns and dies extra long?
Do any of you have these or another 38-40 to compare too?
Also the cylinder throats on that Ruger are only .397" er so and barrel is a fat .401" not the best of conditions fer sure...:confused:

45 2.1
08-12-2006, 08:02 PM
You have a fixable thing there. Older dies set the shoulder back farther and the cases would split at the shoulder from being sized back and blowing forward in a few firings. The chambers on most all the new guns are cut long where the shoulder moves forward out of spec with the cartridge dimensions. I don't have any problems with my RCBS dies in this regard. You need to take a little off the bottom of the sizing die until it firmly touches the shoulder of the fired case that has the shoulder moved forward the least. that should give you the maximum case life for a very thin walled case. Starline cases help in this regard.

Bodydoc447
08-14-2006, 10:00 AM
I might also suggest that you get the throats on the Ruger opened up to .400". I have had that done on my .38-40's from Ruger and it makes a world of difference in the potential accuracy.

Doc

9.3X62AL
08-14-2006, 10:51 AM
Yet ANOTHER caliber that Ruger insisted on screwing up dimensions-wise in their otherwise very fine Blackhawk platforms. The 45 Colt and 44-40 were two others I've heard about.

You might want to check the throats on your 10mm swap cylinder, if the revolver came with one. The 10mm operates at twice the pressures of the 38-40, and you damn sure don't want .397" throats in THAT cylinder.

Bodydoc447
08-14-2006, 12:13 PM
I've got a Buckeye with the .38WCF/10mm conversion and a Davidson .38WCF/.40 S&W conversion. The 10 mm and .40 S&W were right on at .400" Just the .38WCF was undersized. Go figure.

Doc

DOUBLEJK
08-15-2006, 01:50 AM
Yep I think we both went this route with the Ruger 45's Deputy Al...
I don't have cheap access to a .400" reamer like I did for the .453" one so bein' the cheap skate kind I sawed a split in a piece of brass round stock and wrapped it with 320 grit emory cloth and sprayed the chamber down with WD-40 and commenced to turnin' it with a battery powered drill REAL slowly...
After a 10 second lap in each of the 6 holes I cleaned up the cylinder and drove a lead slug thru each of em....as near as I can measure the smallest is now .3987" and the largest is .3994" so I got just about .002 for 10 seconds of cutting with this setup...
Now I'm going to try agin' with that info and turn it for 5 seconds in the small to 3 seconds in the large and hope I don't go much over...
However the barrel slugs right at .402" so a little won't do me in...
The 38-40 model 92 slugs at .4015" so I'm thinkin' dual purpose rounds will be sized at .402" for starters...
I loaded up 5 rounds sized to .401" cast in a RCBS 180 CM mold loaded over 13.0gr of AA#7 lit with a CCI300...these were neck sized Starline cases as my new LEE dies don't reach the shoulder by a very visible amount..
Neway leanin' on the box of my truck at 75 yards all 5 hit a 1 gal. milk jug full of damp sand...this was outa the model 92 and were quite a bit hotter than the Ultramax factory loads as all 5 went thru the jug and none of the 4 factory slugs that hit the jug made it out the other side...

9.3X62AL
08-15-2006, 10:43 AM
2JK--

I would make the same adjustments you came up with, right on the dot.

Again, I stress that I have had no experience with the 38-40, but quite a bit with the 32-20 and 44-40. In both revolvers and rifles, these cases really get "modified" by the act of firing--shoulders (such as they are) get blown forward, chambers have kinda wide radial clearances, too. And these variances aren't constant between different platforms--oh, not at all--pure poetry here. The ideal with these hyphenated Winchester calibers from the Old West was to carry revolver and rifle in the same chambering, and that would likely work with factory loads as far as getting rounds into chambers went. But to get decent accuracy, you REALLY have to tailor the ammo to each gun's chamber quirks if decent accuracy is to be expected. This involves different sizing die adjustments for each gun, and often different boolit sizes as well. I used to think that CAS shooters who resorted to 45 Colt and 38 Special lever rifle/revolver combos were sort of "cheating" by going the straightwall route--that wasn't fair of me, they are just trying to un-complicate a rather daunting dimensional challenge.

Harry O
08-15-2006, 09:42 PM
I had the same problem. You might want to read this. BTW, I have made up a second set of shortened dies and found that shortening them by 0.075" is plenty. My first try at 0.125" worked, but it worked the brass more than necessary.

http://www.leverguns.com/articles/neck_lengths.htm

DOUBLEJK
08-16-2006, 12:33 PM
Harry
That's a fine article you did that gave me some more to ponder while I get aquainted with this very improved case I'm getting after firing....
Sure was a WOW LOOK AT This when I fired the first one...:roll:
My rifle has a chamber just a tad longer than my revolver but not so much that a little push when loadin' the revolver still chambers the cartridge...
I am going to trim the sizing die to match the rifle as near as I can which will give me a bit more than 1/16" more sized neck...It will also make the neck that is sized almost grip the full length of my RCBS180CM boolit that is my only mold for this right now...I liked the fact it has a crimp groove and it seems to be going to shoot with my limited test a couple days ago...
Sure would be interested in your loads if yer willin' to share em as not much is out there for this un'...J. Taffin had a good article and as always ole K. Waters did a good one also...
I am goin' to work up loads from cat sneeze to close to the old H.V. loads just because it will be a relaxin' good time....[smilie=w:
The loads I'll probably end up using most will be the lite ones as I plink 1000's of rounds more than I shoot at game....

9.3X62AL
08-16-2006, 04:04 PM
Harry's article text is a MUCH better and more detailed description of what I was driving at--thanks for another look at that piece, Harry.

Harry O
08-16-2006, 07:34 PM
DoubleJK: My loads are pretty simple. So far, I have pretty much stuck to black powder. The stock 40043 bullet (this is a little earlier than the 40143) compresses the BP a little and there is enough lube to work in revolvers. I have had a little problem with those loads in a Uberti Winchester 73 replica with a 24" barrel, though. It seems to run out of lube by the last 2 or 3 inches of barrel. I have had good luck with a lube wad under the bullet, but it is a lot of extra work.

I have shot a little bit of Unique with the 401452 bullet. I have tried 6.5gr (both revolver and rifle) to 9.5gr (revolver only) without any particular load jumping out as best. All were accurate. This is the bullet to use with smokeless. It has a crimp groove. The 40143 does not have a crimp groove and I had a problem with some of them being pushed back into the neck when loaded into the rifle. I don't believe I shot more than one or two before quitting. That is not a problem with the revolver, though. You can use either bullet with smokeless.

Harry O
08-18-2006, 08:44 PM
Don't have pictures yet of my 38-40 revolvers (3 of them, but one has been converted to 41 Long Colt). However, here is a picture of the 38-40 rifle (the upper one -- really it is further from the camera lens). It is a Uberti copy of the Winchester 73 with a tang sight. I have almost excelusively used Black Powder in it. The one in the foreground is a Winchester 94 BB in .375 Win.

http://gallery.sixshootercommunity.org/albums/userpics/10013/normal_IMG_0081.JPG

DOUBLEJK
08-18-2006, 10:21 PM
Nice lookin' iron there...love that farther one...:mrgreen:
I hit a snag on my project here...
That dang Ruger cylinder got harder n harder.....1st lap session suggested it would be a piece a cake as fast as it opened up...musta just been some tool marks er grooves as it now ain't movin' much material at all...ran my battery dry and used up bout 4' a 320 grit cloth and can't see much enlargement here...sure is smooth n shiny in my cylinder throats tho...[smilie=1:

Lloyd Smale
08-20-2006, 06:43 AM
my smith 4440 was the same way and trimming the dies like was suggested here did the trick

DOUBLEJK
08-27-2006, 11:07 PM
Got it out fer some exersize this mornin' and it is still going bang so I musta not messed it up too bad...have the throats at about .400" now and shot some Winchester factory loads into 2" at 25yds... my RCBS 180 CM loaded a bit warmer than the factory stuff went about 3 1/2" at the same range...:Fire:
I need to lap out my boolit sizin' die too.... I think .4015" might improve things over the .401" as I get these throats opened up...
Anybody know why Winchester crimps the primers on thier factory loads...seems like an extra step that adds expense would not be done fer no reason...???:confused: